Lead frame casing

ABSTRACT

A lead frame casing for housing a stack of lead frame strips. The casing includes a central volume-defined between substantially rigid members and resilient members. The former define at least one reference plane and the latter are deflected toward the former when a lid is placed over the casing to align the strips of the stack against the reference plane and immobilize the stack to prevent damage during transport and handling of the casing and to facilitate handling of the lead frames by automated equipment.

This is a continuation of application Ser. No. 08/587,641, filed Jan.17, 1996, U.S. Pat. No. 5,836,454.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an apparatus and a method for loadingand storing lead frames such as are employed for the physical supportand electrical connection of semiconductor devices. In particular, thepresent invention relates to a lead frame casing mechanism that alignsand immobilizes lead frames within the casing against a reference plane,for prevention of damage to the lead frames and ease of unloading byautomatic mechanisms as employed in the art.

2. State of the Art

Integrated circuit (IC) semiconductor dies, also termed "chips," areenclosed in packages that provide protection from hostile environmentsand enable chip electrical interconnection to printed-circuit boards andother components. Lead frames are widely used in the packaging ofsemiconductor dies, for physical support of the die and to provideconductors for the die to the exterior of the package, which may be atransfer-molded plastic package, a ceramic package, a so-called "globtop" package, or other package structure known in the art.

Included within each lead frame of a conventional design are a pluralityof leads and a central die attach pad area, typically termed a paddle,tab or island. The die attach pad area may be downset from the planedefined by the leads. With such a design, when a die is attached on thepad area, the top or active surface of the die is substantiallyco-planar with the leads of the lead frame so that bond wire lengthsbetween the bond pads on the active surface and the inner lead ends areminimized. With other conventional lead frame designs, the entire frameis co-planar, and longer bond wires are employed to connect the bondpads on the active surface of the die with the inner ends of the leads.Another variation of lead frame design is the so-called leads-over-chip,or LOC, design, which eliminated the central die attach area andadhesively suspends the die by its active surface from a number of leadsextending over the active surface.

In practice, a plurality of laterally adjacent lead frames are etched orstamped from a strip of metal, the frames remaining secured togetherthrough the packaging or encapsulation step of the fabrication process.This intermediate structure is commonly known as a "lead frame strip."The number of lead frames fabricated within each lead frame stripvaries, depending on the size of the individual lead frames and theequipment and materials for processing them to attach the dies, wirebond and encapsulate the devices.

Lead frames are often fabricated by a vendor to the semiconductor devicefabricator, rather than by the fabricator itself. The lead frames arestamped or etched, as noted above, and then shipped to the fabricatorfor die attachment, wire bonding, and encapsulation. At a minimum, thelead frame strips may be bundled, wrapped in thin paper or plastic wrap,and placed into a shipping tray. Layers of paper or plastic may beinterposed between strips for additional protection. Conventionalshipping trays consist of a flat bottom, two sets of opposing sides, andan open top. Within the tray, one or more movable partitions may beprovided for accommodating the adjacent bundles of lead frame strips.Alternatively, stuffing materials may be included within the tray toaccommodate the lead frame strips.

U.S. Pat. No. 4,798,305 issued Jan. 17, 1989 to Laverty discloses avariety of prior art shipping trays, including a tray design withmovable partitions to accommodate different sizes and quantities of leadframes.

U.S. Pat. No. 5,125,509 issued Jun. 30, 1992 to Takei et al. discloses arectangular lead frame container including a container body and asnap-on lid, the container body optionally including fixed or rigidprojections or protrusions from the side walls to abut a stack of leadframes in the container.

A more complex shipping tray, also termed a "magazine", is described inU.S. Pat. No. 5,310,055 issued May 10, 1994 to Chu. The Chu patentprovides a magazine for automatically collecting lead frame stripsdispensed from an automated lead frame quality inspection machine. Themagazine includes a cover that is placed over the magazine to provide apackaging tray for shipment of the collected lead frame strips. Aplurality of holes are positioned within the base of the magazine. Themagazine holes are positioned to lie directly underneath index holeswithin the lead frame strips when the lead frame strips are stackedinside the magazine. To prevent movement of the lead frame strips withinthe magazine during shipment, pins are inserted vertically into theindex holes of the lead frame strip and through the magazine holes.Similarly-aligned holes to receive the pin tops are also included in ashield covering the top lead frame strip to protect the lead frame stackfrom oxidation and contamination.

The prior art shipping trays and containers of Laverty and Takei do notprovide positive alignment of the lead frame strips against a referenceplane, and their construction dictates that a snug fit or abutment ofthe lead frame strips against the partitions or projections may damagethe strips if they are forced into the volume provided in the tray orcontainer. If some clearance is allowed between the partitions orprojections and the strips, movement is thereby permitted and damage mayalso ensure in that situation.

The prior art tray of Chu utilizing indexing pins to immobilize a leadframe strip stack has a significant disadvantage from a productionstandpoint, since any change in the positioning of the index holeswithin the lead frame strips requires a change in the production moldfor the magazine and shield. Additionally, the pin alignment mechanismrequires removal of the pins in order to release the lead frame stripsfrom the tray for pick up by a strip unloading apparatus.

Therefore, it would be advantageous to develop a lead frame casing thataligns at least one side of a vertical stack of lead frame stripsagainst a common reference plane and prevents any motion of the leadframe strips within the casing during shipment to avoid damage, butwhich still permits easy release and removal of the lead frame stripsfrom the casing. It would be a further advantage to develop a lead framecasing design which is adaptable to permit immobilization of lead framestrips having assorted lengths and widths as well as index hole patternswithout significant design changes, the use of different-sizedpartitions, or additional parts such as indexing pins.

SUMMARY OF THE INVENTION

The present invention relates to an apparatus and a method for loading,aligning and storing lead frame strips. The apparatus includes at leasta casing and a lid. The casing includes a base, which provides a supportfor the collected lead frame strips, which are stacked in mutuallysuperimposed relationship. Two opposing and mutually parallel side wallsand two opposing and mutually parallel end walls oriented transverselyto the side walls extend upwardly from the base to form an enclosurearound the lead frame strips housed in the casing. The enclosure createdby the side and end walls is open at the top to provide access into thecasing.

The casing interior also includes one or more substantially rigidvertical columns, and preferably three such columns, against which thelead frame strips are aligned in at least one, and preferably two,common reference planes as they are introduced into the casing. One ormore flexible or resilient vertical columns are laterally spaced fromthe substantially rigid columns within the casing in opposition to oneor more of the rigid columns and defining, with the rigid columns, acasing volume in which the lead frame strip stack is contained. Anoptional but preferred feature of the invention is a support platedisposable in the bottom of the casing over the base and within the leadframe strip casing volume to support the lead frame stack from below andprovide a means for lifting the stack from the bottom of the casing forunloading, as by a robotic or other automatic unloading apparatus. Inthis case, an aperture of slightly smaller lateral dimensions than thesupport plate is provided in the base of the casing.

The lid is substantially flat or planar, adapted for placement on thecasing and substantially covers the stacked lead frame strips bycovering the top opening of the casing. The lid includes one or moreangled steps of a like number to the flexibly mounted columns and thatare positioned to come into contact with the upper ends of the flexibleor resilient columns extending from the casing when the lid is securedthereon, such as by sliding, pressing (snap-on) or similar known lockingmechanism. By closing the casing with the lid, such as by sliding thelid onto the top of the casing, the angled steps come into contact withthe flexible or resilient columns, forcing those resilient columns in apivotal manner toward their opposing, cooperating rigid columns andthereby immobilizing the stack of lead frame strips located between therigid and resilient columns.

BRIEF DESCRIPTION OF THE DRAWINGS

The advantages, as well as other novel and important features of thepresent invention will be better understood when the followingdescription is read along with the accompanying drawings of which:

FIG. 1 is a top view of a preferred embodiment casing according to thepresent invention, which illustrates the placement of the rigid columnsand the resilient columns within the casing with respect to a containedlead frame strip;

FIG. 2 is a side view of the casing of FIG. 1, which illustrates theorientation and placement of the rigid vertical columns and the movablevertical columns within the casing;

FIG. 3 is a sectional side view of the casing of FIG. 1 taken along line3--3 of FIG. 1;

FIG. 4 is a side view of a preferred embodiment of the lid according tothe present invention, which illustrates the placement and configurationof the angled steps coupled to the lid;

FIG. 5 is a bottom view of the lid, which illustrates the placement andconfiguration of the angled steps coupled to the lid;

FIG. 6 is a top view of an optional support plate placed beneath thelead frame stack within the casing;

FIG. 7 is a side view of the support plate of FIG. 6; and

FIG. 8 is a top view of an exemplary lead frame strip to be contained bythe casing of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, a top view of a lead frame casing 10 according tothe present invention is shown. A plurality of exemplary lead framestrips 12 are shown vertically stacked in casing 10. Details of the leadframe strip are shown in FIG. 8. The casing 10 includes a flat base 14having a longitudinal aperture 15 therein (shown in broken lines), twoopposing, mutually parallel planar side walls 20 extending verticallyupwardly from base 14, and two opposing, mutually parallel end walls 21extending vertically upwardly from base 14 and joined to the side walls20 at the corners of the casing 10. Circular clearance hole 17 in base14 is used for correct positioning and identification of "Pin One" onthe lead frames by automated equipment. A plurality of rigid verticalcolumns 16a, 16b and 16c extend vertically upwardly from the base 14,and a plurality of flexible, resilient or movable vertical columns 18a,18b and 18c extend vertically upwardly from the base 14 in spacedlateral relationship to their respectively cooperating rigid verticalcolumns, as will be explained hereafter.

In a preferred embodiment, the two side walls 20 will have slopedinterior edges 22, which slope downwardly from the top edges of thewalls 20 and terminate proximate the base 14 (see FIG. 2). The slopededges 22 define one, and preferably two, opposing openings 23, whichprovide lateral access to the interior of the casing 10 and facilitatehandling of the lead frame strips 12 during loading and unloading of thesame from the casing 10. A cut-out 34 is included on the upper region ofone of the end walls 21, the cut-out 34 thus creating a clearance whichpermits the entry of an angled step 62c protruding from a lid 60 (FIG.4) to the interior of the casing 10 before the lid 60 is completelylongitudinally slid onto the top of casing 10.

The plurality of rigid vertical columns 16a, 16b and 16c each preferablyinclude a rib segment 30 which lies in substantially perpendicularorientation with respect to the side or end wall to which that verticalcolumn 30 is coupled, and a flange segment 32, which lies substantiallyperpendicular to the rib segment and substantially parallel to the sideor end of the stack of lead frame strips 12 which it abuts when a stackis loaded in the casing. The flange segments 32 create at least onevertical reference plane R1, and preferably first and second verticalreference planes R1 and R2, for mutually aligning a side and an end ofeach strip of the stacked lead frame strips 12 within the casing 10.

Laterally spaced from and on an opposing side or end of the lead framevolume from each of the rigid vertical columns 16a, 16b and 16c,respectively lies one of the plurality of flexible, resilient or movablevertical columns 18a, 18b and 18c in substantially parallel relationshipto its associated rigid column. The respective placement of the movablevertical columns 18 and the rigid vertical columns 16 form a rectangularboundary defining the lateral boundaries of a central lead frame volumeV, which volume is marginally longer and wider than the lead framestrips 12 to be inserted into the casing 10. The plurality of flexibleor resilient vertical columns 18a, 18b and 18c guide the lead framestrips 12 into the lead frame volume V of the casing 10 defined by thecolumns 16 and 18, and generally align the lead frame strips 12 againstthe reference planes R1 and R2 created by the flange segments 32 of theplurality of rigid vertical columns 16.

In a preferred embodiment, casing 10 may be approximately 2.5 inches inwidth, 8.0 inches in length, and 2.0 inches in height, although specificdimensions are, of course, variable with the size and number of leadframe strips 12 to be accommodated by casing 10. The rectangularboundary formed by the rigid vertical columns and the movable verticalcolumns is dictated by the length and width of the lead frame strips 12to be stacked in volume V. Thus, the placement of the rigid verticalcolumns 16 and the movable vertical columns 18 varies according to thesize of the lead frame strips 12 to be loaded.

Referring to FIG. 2, a side view of the casing 10 according to thepresent invention is shown, illustrating the placement and configurationof the plurality of rigid vertical columns 16a, 16b and 16c and one ofthe plurality of movable vertical columns 18c within the casing 10. Eachof the plurality of rigid vertical columns 16a, 16b and 16c are joinedto one of the plurality of side walls or end walls at a first point 24(FIG. 2), and are coupled to the base 14 at a second point 26 (FIG. 2).

Referring to FIG. 3, an enlarged, sectional side view along the line3--3 of FIG. 1 of the casing 10 is shown, illustrating a section of therigid vertical column 16a and a flexible or resilient, also termedmovable, vertical column 18b in some detail. The flange segment 32 ofeach of the plurality of rigid vertical columns 16 includes a beveled,chamfered, radiused or otherwise tapered tip 40 for guiding the adjacentside or end of each one of the plurality of lead frame strips 12 beingloaded into casing 10 towards the center of the casing and volume V. Thebeveled tip 40 of the parallel segment 32 will slope downwardly andtoward the center of the casing 10. Preferably, the height of the ribsegment 30 is less than the height of the corresponding flange segment32 of each of the plurality of rigid vertical columns 16 to permit thepassage of locking tabs on the underside of the lid 60 thereover.

As shown here, the flexible or resilient vertical column 18b includes athin web segment 44 at a point where the column 18 is joined to the base14. This construction is illustrative of that of all of the columns 18.The web segment 44 imparts added flexibility to the vertical column 18,acting as a resilient hinge. Preferably, the web segment 44 is shaped sothat the height H of the web segment 44 is greater than the depth D ofthe web segment 44, although this is not required. In a preferredembodiment, the height H of the web segment 44 is 1.25 to 2.50 timesgreater than the depth D of the web segment 44. While such ratios ofheight to depth are desirable, it should be understood that any websegment of suitable height, width and depth imparting flexibility to themovable vertical column 18 is acceptable. For torsional rigidity of thecolumns 18 it is preferred, although not required, that the width W (seeFIG. 1) of the web segments is coextensive with that of the main body ofthe columns extending upwardly therefrom, so that contact with an angledstep 62 as subsequently described will cause deflection, rather thanrotation, of the column 18.

Each of the plurality of movable vertical columns 18 also includes abeveled, chamfered, radiused or otherwise tapered tip 46 for guidingeach one of the plurality of lead frame strips 12 towards referenceplanes R1 and R2 bounding volume V at the center of the casing. Thetapered tip 46 of each movable vertical column 18 will slope downwardlyand toward the center of the casing 10.

Each of the plurality of movable vertical columns 18 further includes aproximal side 50, which faces the center and volume V of the casing 10,and a distal side 52, which faces away from the center of said casing10. The proximal side 50 is sloped upwardly and away from the center ofthe casing 10. Exemplary column 18b is shown in FIG. 3 in a deflected orinwardly-rotated position as it would reside against a stack of leadframe strips 12 disposed in volume V. A first reference axis 54 and asecond reference axis 55 for column 18b are shown in FIG. 3, both ofwhich axes lie in substantially perpendicular orientation with respectto the base 14. The proximal side 50 extends along an axis 56 orientedwith respect to the second reference axis 55 at an angle 57 whichpreferably is within about 0.5° when column 18b is biased against thestack of lead frame strips. The distal side 52 is sloped upwardly andtoward the center of the casing 10. The distal side 52 extends along anaxis 53 oriented with respect to the first reference axis 54 at an angle58 which is preferably within about 2° to 4° when column 18b is biasedagainst the stack of lead frame strips. A dotted representation 18' offlexible or resilient vertical column 18b is shown, illustrating column18b in a relaxed or non-deflected position, prior to being contacted bythe angled steps 62 of the lid 60, as further described in FIGS. 4 and5. The foregoing angular relationships preferably apply to all columns18.

FIG. 4 is a side view of the lid 60, having a top 70 and a bottom 72.The lid 60 includes a plurality of angled steps 62a, 62b and 62cprotruding downwardly (as lid 60 is employed with casing 10) from thebottom 72 of the lid 60. The plurality of angled steps 62 arepositioned, as shown in FIG. 5, so as to contact the correspondingplurality of flexible or resilient vertical columns 18a, 18b and 18c ofthe casing 10. The plurality of angled steps 62a, 62b and 62c eachinclude a slightly angled or tapered inner side 74, which faces thecenter of said lid 60 and which is sloped outwardly and away from thecenter of said lid 60. A third reference axis 68 is shown in FIG. 4,which lies in substantially perpendicular orientation with respect tothe bottom 72 of the lid 60. The inner side 74 extends along an axis 66oriented with respect to the third reference axis 68 at an angle 69which is preferably about 4° to 5°. Lid 60 includes a circular hole 71,alignable with hole 17 when lid 60 is secured to casing 10, forpositioning and identification purposes.

Referring to FIG. 5, a bottom view of the lid 60 is shown, illustratingthe placement of the angled steps 62a, 62b and 62c coupled to the lid60. The lid 60 will typically have a width and length adapted to matchthe top opening of the casing 10 so as to substantially cover the casing10 to its outer perimeter. In a preferred embodiment as employed withcasing 10, the lid 60 has a width of 2.5 inches, a length of 8.0 inches,and an approximate thickness of 0.16 inches. However, it should beunderstood that the size of the lid 60, as well as the placement of theplurality of angled steps 62 may vary according to the size of casing 10and the placement of the plurality of movable vertical columns 18 in thecasing 10.

Referring to FIG. 6, a top view of a support plate 80 is shown. Thesupport plate 80 comprises a substantially planar surface 82 adapted tosupport a vertically-stacked plurality of lead frame strips 12. Thesupport plate 80 will typically have a width and length substantiallycorresponding to the length and width of the lead frame strips 12.Preferably, the support plate 80 will have a width and length that issimilar to the width and length of the lead frame strips 12 supportedthereon. It should be understood that the width and length of thesupport plate 80 will vary as the overall casing design dictates.

FIG. 7 is a side view of the support plate 80. In a preferredembodiment, the support plate 80 is about 0.05 to 0.10 inches inthickness. However, it is understood that the thickness of the supportplate 80 may vary according to its material and to the weight and numberof lead frame strips 12 to be carried thereon. The support plate 80should be of sufficient torsional and bending rigidity for support ofthe lead frame strips during loading and unloading of the lead framestrips 12. As previously noted, support plate 80 is sized to extendbeyond the boundaries of the aperture in base 14.

The lid 60 is secured to the top of lead frame casing 10 of the presentinvention by a snap-lock or slide-lock mechanism as known in the art. Byway of example only, casing 10 may include a plurality ofinwardly-projecting tabs 90 as shown in FIGS. 1 and 2. Tabs 90 areengaged by resilient clips 92 on the underside of lid 60 when lid 60 isslid over the top of casing 10 from left to right, as the drawingfigures are oriented. Other locking mechanism as known in the art arealso contemplated as having utility with the invention.

In use, the casing 10 is loaded with suitably sized lead frame strips12, strips 12 being parallel to the base 14 of casing 10 and insubstantially superimposed mutual relationship. Typically, 150 to 200lead frame strips 12 would be stacked in a casing, unless paper orplastic strips are interleaved with the lead frame strips 12, in whichcase the number of strips 12 would be reduced. When the casing 10 isfully loaded, lid 70 is placed over casing 10 so that the resilientclips 92 extend into the casing interior and are to the right of theirrespective tabs. The lid 60 is then slid to the left as noted aboveuntil tabs 90 are engaged by resilient clips 92 in a "snap-lock" or"slide lock" connection. As lid 60 slides over casing 10 and tabs 90 andclips 92 engage, angled steps 62a, 62b and 62c respectively engage thedistal sides 52 of each of their associated columns 18a, 18b and 18c,and rotationally deflect columns 18 about 2° to 4° toward volume V sothat their proximal sides 50 are substantially vertical and adjacentlead frame strip stack, in the process aligning one side and one end ofeach of the lead frames in the stack with references planes R1 and R2,respectively. As noted with respect to FIGS. 1 and 2, cut-out 34 permitsstep 62c to enter the interior of casing 10 from the end of the casing10 as lid 60 slides to the left.

The casing 10 and lid 60 of the invention are preferably fabricated fromor coated with an anti-static material, and most preferably is formed ofa molded non-metal such as a synthetic resin, examples of which includepolypropylene, polyethylene, an olefin series resin such as a copolymerof the foregoing materials, a polyacetal resin, or an ABS resin. Manyother suitable materials having desirable characteristics for the casingand lid (strength, impact-resistance, transparency, etc.) are also knownin the art.

The lid 60 and casing 10 are preferably injection-molded using a mastermold defining the outer casing dimensions and having relocatablesegments to relocated columns 16 and 18 on the casing interior to definevarious sizes of volume V for different lengths and widths of lead framestrips 12 which a particular casing 10 is intended to accommodate. Themold for lid 60 may similarly include relocatable segments to moveangled steps 62 to correspond to relocated columns 18. It iscontemplated that only one set of columns, for example fixed or rigidcolumns 16, may be relocated to vary the length and width of volume V.In such a case, flexible columns 18 and angled steps 62 may bepermanently placed. Alternatively, only flexible columns 18 and steps 62may be relocated.

Variations of the illustrated preferred embodiment are numerous andcontemplated as being within the scope of the invention. For example,more than two columns may be employed along each side of the casingvolume V; the lid 60 may be designed to snap vertically down over casing10 and deflect columns 18 inwardly; the proximal sides of the columns 16and 18 may be arcuate rather than flat; the casing may be formed withlow or no side and end walls and the lid may be formed with side and endwalls which extend over the columns and the lead frame stack and engagethe base; the casing may be formed with an open end and the lid includea downwardly-protruding column in lieu of column 18c which engages theright-hand end of the lead frame stack when the lid slides from left toright and aligns the opposing end of the stack against column 16c andreference plane R1; rigid columns 16 may be supported by buttressesfixed to the base 14 of the casing 10 rather than the walls; acontinuous inner rigid wall may be employed along one side of volume Vinstead of columns if the lateral access to the strips is required; asingle resilient inner wall may be employed along one side of volume Vin like manner.

While the present invention has been described in terms of certainembodiments, it is not so limited, and those of ordinary skill in theart will readily recognize and appreciate that many additions, deletionsand modifications to the embodiments described herein may be madewithout departing from the scope of the invention as hereinafterclaimed.

What is claimed is:
 1. A container for receiving a plurality of leadframe strips in a vertical stack, comprising:a base extendingtwo-dimensionally and substantially in a single plane; at least onesubstantially rigid member extending transversely upwardly from saidbase and defining at least one reference plane adjacent a volume abovesaid bases within which volume said stack is to be received; at leastone resilient member coupled to said base and extending transverselyupwardly from said base and adjacent said volume for biasing saidplurality of lead frame strips of said stack toward said at least onereference plane; and structure for deflecting said at least oneresilient member toward said volume.
 2. The container of claim 1,wherein said at least one substantially rigid member comprises aplurality of spaced rigid members.
 3. The container of claim 1, whereinsaid at least one resilient member comprises a plurality of spacedresilient members.
 4. The container of claim 1, wherein said deflectingstructure comprises elements carried on a lid disposable over, andlockable to, said base. strips in a container, comprising:providing acontainer having a base; vertically stacking said plurality of leadframe strips over said base within said container; substantiallyaligning a first side of each of said vertically stacked plurality oflead frame strips with a common reference plane; and deflecting at leastone resilient member coupled to said base and extending upwardly andtransversely from said base toward a second side of said verticallystacked plurality of lead frame strips to immobilize said verticallystacked plurality of lead frame strips.
 5. The container of claim 4,further including a plurality of walls extending upwardly from saidbase, and to which said lid locks.
 6. The container of claim 1, whereinsaid at least one substantially rigid member comprises a plurality ofsubstantially rigid members located along a major axis of said volume,and a single substantially rigid member located at a first end of saidvolume, and said at least one resilient member comprises a plurality ofresilient members located along said major axis of said volume and inopposition to said substantially rigid members located along said majoraxis and a single resilient member located at a second end of saidvolume.
 7. The container of claim 6, further including means fordeflecting said resilient members toward said volume.
 8. The containerof claim 7, wherein said deflecting means comprises elements carried ona lid disposable over and lockable to said base.
 9. The container ofclaim 8, further including a plurality of walls extending upwardly fromsaid base, and to which said lid locks.
 10. The container of claim 1,wherein said at least one reference plane comprises two mutuallyperpendicular reference planes, one reference plane extending along aside of said volume and the other reference plane extending along an endof said volume.
 11. The container of claim 1, further including anaperture in said base below said volume, and a support plate disposedover said aperture.
 12. A method of aligning and immobilizing aplurality of lead frame strips in a container, comprising:providing acontainer having a base; vertically stacking said plurality of leadframe strips over said base within said container; substantiallyaligning a first side of each of said vertically stacked plurality oflead frame strips with a common reference plane; and deflecting at leastone resilient member coupled to said base and extending upwardly andtransversely from said base toward a second side of said verticallystacked plurality of lead frame strips to immobilize said verticallystacked plurality of lead frame strips.
 13. The method of claim 12,further comprising substantially aligning the same end of each of saidstrips against a common reference plane before substantiallyimmobilizing said aligned stack within said container.